Nathan's original review continues below.

Amazon’s recent rejig of its ever-expanding Echo and Alexa product range ran the full gamut of its smart-home products, but the most interesting of the bunch was the Echo Plus.

It might look like just a warmed-up Echo, but don’t let that fool you: Amazon’s staffers have been hard at work adding new features and refining the Echo’s capabilities, including better audio processing, enhanced smart-home features, and improved far-field microphone tech.

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Amazon Echo Plus review: What you need to know

The Echo Plus is much the same as before. Again, it’s controlled by your voice, can play music and cast video to your Fire TV Stick, control your smart-home devices and act as your own personal digital assistant.

It’s a larger device than the dinkier Echo 2 , with a handful of new features including improved speaker drivers, a better microphone and a smattering of new smart-home capabilities (more on that later).

Amazon Echo Plus review: Price and competition

Amazon’s Echo Plus can be picked up for £140. It’s available in three colours – black, silver and white – and you can grab the speaker with a Philips Hue bulb for the same price as a speaker-only package, which we can only assume is a limited offer.

The speaker itself doesn’t face any direct competition – as there are no other smart home speakers that offer Alexa’s services and a smart-home hub. However, it would be silly to ignore the Echo Plus’ alternatives.

For starters, there’s the fresh-faced Echo 2. This is a more compact variant of the Echo Plus, costing much less at £90 , but it doesn’t offer the same built-in ZigBee IoT connectivity. Then there’s Google Home for £129 . This smart-home speaker runs Google Assistant instead of Alexa and it’s smaller, but again doesn’t offer dedicated smart-home connectivity.

Amazon Echo Plus review: Design

While the fabric-coated Echo 2 saw a drastic size reduction, the Echo Plus is much the same as the original. In fact, it’s so similar to 2014’s Blade Runner-esque monolith, I could have just grabbed this section from the original review, and you’d be none the wiser.

The Echo Plus has the same two-button setup as before, with an array of seven microphones inside and a blue LED ring circling the top. The speaker grilles are located at the bottom of the device, with a 2.5in downward-firing woofer and a 0.8in tweeter lurking behind the grilles, for better audio processing.

Amazon Echo Plus review: Sound quality

With the addition of Dolby processing and improved speaker drivers, the Echo Plus’ audio quality is a good deal more impressive than the aged Echo’s. While the previous model failed to produce bass and mid-bass notes, this new model produces warmer, richer and much more enjoyable music. The fact that there is evidence of bass this time alone is excellent, and the Echo Plus certainly doesn’t overdo it like Google’s incessantly bass-heavy Home.

I’m in no way suggesting that the Echo Plus is perfect. In fact, certain acoustic tracks and classical numbers sounded a touch boomy around the mids on occasion, but the Echo Plus is a far cry from the harsh and tinny sounds produced by the original.

And finally, as for the speaker’s improved far-field microphone array, I can’t say anything has improved. At least I couldn’t notice a difference: the original’s effort was so good that it barely needed improving anyway.

Amazon Echo Plus review: Smart home

So, what does this extra smart-home connectivity allow you to do? Effectively, to connect to and manage your existing ZigBee-compatible lightbulbs, thermostats and so on. The Echo Plus can discover and control these compatible devices directly, without the need to add discrete Alexa “Skills”.

The process is simple enough in theory. Say “Alexa, discover my devices” and the speaker will automatically search for compatible devices in the vicinity and create a hub where the devices can be managed.

Alas, the initial setup is not quite as simple as Amazon seemed to suggest at the unveiling. Yes, you can ask the Echo Plus to discover your devices as soon as you pull it out of the box, but you’ll have to reset ALL of your smart-home appliances and put them in pairing mode before Alexa picks them up. This certainly isn’t ideal, especially if you have as many smart lightbulbs and plugs as I have.

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However, the list of compatible devices is pretty big. There are Philips’ Hue lightbulbs, plus products from the Belkin WeMo range and from TP-Link, Hive, Nest, Samsung SmartThings, Netatmo and Tado among others. You’ll find a full list of Alexa-compatible devices on Amazon’s website.

Amazon didn’t stop there, though. With the Echo Plus’ greater focus on music, Alexa can now play music across different devices in various rooms. As long as the Echo products are connected to the same network, you can play Amazon Music, TuneIn and Spotify across all devices.

There’s also hands-free calling and messaging via Alexa Calling, a feature that will also come as a software upgrade to the older Echo devices. And, in early 2018, the Echo Plus will gain the ability to make and receive landline calls via an extra piece of hardware – the Echo Connect.

Amazon Echo Plus review: Verdict

The first Amazon Echo was a breakthrough product, but the Echo Plus extends the product’s reach even further and begins to lay the groundwork to completely revolutionise the home.

The Echo Plus works as seamlessly as Amazon promises – as do the rest of Amazon’s Alexa-powered products for that matter – offering a smattering of welcome new features, and improving on the sound quality of the original.

Of course, if you’re not interested in all the smart-home stuff, you can save yourself considerable money and get the all-new Echo for £90, or even the non-speaker Echo Dot for £50. But, for me, the Echo Plus is the most interesting of all Amazon’s new products. It’s sensibly priced, and offers a significant improvement over the original.